xref: /openbmc/linux/drivers/net/wireless/ti/wlcore/rx.c (revision 612a462a)
1 /*
2  * This file is part of wl1271
3  *
4  * Copyright (C) 2009 Nokia Corporation
5  *
6  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * version 2 as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20  * 02110-1301 USA
21  *
22  */
23 
24 #include <linux/gfp.h>
25 #include <linux/sched.h>
26 
27 #include "wlcore.h"
28 #include "debug.h"
29 #include "acx.h"
30 #include "rx.h"
31 #include "tx.h"
32 #include "io.h"
33 #include "hw_ops.h"
34 
35 /*
36  * TODO: this is here just for now, it must be removed when the data
37  * operations are in place.
38  */
39 #include "../wl12xx/reg.h"
40 
41 static u32 wlcore_rx_get_buf_size(struct wl1271 *wl,
42 				  u32 rx_pkt_desc)
43 {
44 	if (wl->quirks & WLCORE_QUIRK_RX_BLOCKSIZE_ALIGN)
45 		return (rx_pkt_desc & ALIGNED_RX_BUF_SIZE_MASK) >>
46 		       ALIGNED_RX_BUF_SIZE_SHIFT;
47 
48 	return (rx_pkt_desc & RX_BUF_SIZE_MASK) >> RX_BUF_SIZE_SHIFT_DIV;
49 }
50 
51 static u32 wlcore_rx_get_align_buf_size(struct wl1271 *wl, u32 pkt_len)
52 {
53 	if (wl->quirks & WLCORE_QUIRK_RX_BLOCKSIZE_ALIGN)
54 		return ALIGN(pkt_len, WL12XX_BUS_BLOCK_SIZE);
55 
56 	return pkt_len;
57 }
58 
59 static void wl1271_rx_status(struct wl1271 *wl,
60 			     struct wl1271_rx_descriptor *desc,
61 			     struct ieee80211_rx_status *status,
62 			     u8 beacon)
63 {
64 	memset(status, 0, sizeof(struct ieee80211_rx_status));
65 
66 	if ((desc->flags & WL1271_RX_DESC_BAND_MASK) == WL1271_RX_DESC_BAND_BG)
67 		status->band = NL80211_BAND_2GHZ;
68 	else
69 		status->band = NL80211_BAND_5GHZ;
70 
71 	status->rate_idx = wlcore_rate_to_idx(wl, desc->rate, status->band);
72 
73 	/* 11n support */
74 	if (desc->rate <= wl->hw_min_ht_rate)
75 		status->encoding = RX_ENC_HT;
76 
77 	/*
78 	* Read the signal level and antenna diversity indication.
79 	* The msb in the signal level is always set as it is a
80 	* negative number.
81 	* The antenna indication is the msb of the rssi.
82 	*/
83 	status->signal = ((desc->rssi & RSSI_LEVEL_BITMASK) | BIT(7));
84 	status->antenna = ((desc->rssi & ANT_DIVERSITY_BITMASK) >> 7);
85 
86 	/*
87 	 * FIXME: In wl1251, the SNR should be divided by two.  In wl1271 we
88 	 * need to divide by two for now, but TI has been discussing about
89 	 * changing it.  This needs to be rechecked.
90 	 */
91 	wl->noise = desc->rssi - (desc->snr >> 1);
92 
93 	status->freq = ieee80211_channel_to_frequency(desc->channel,
94 						      status->band);
95 
96 	if (desc->flags & WL1271_RX_DESC_ENCRYPT_MASK) {
97 		u8 desc_err_code = desc->status & WL1271_RX_DESC_STATUS_MASK;
98 
99 		status->flag |= RX_FLAG_IV_STRIPPED | RX_FLAG_MMIC_STRIPPED |
100 				RX_FLAG_DECRYPTED;
101 
102 		if (unlikely(desc_err_code & WL1271_RX_DESC_MIC_FAIL)) {
103 			status->flag |= RX_FLAG_MMIC_ERROR;
104 			wl1271_warning("Michael MIC error. Desc: 0x%x",
105 				       desc_err_code);
106 		}
107 	}
108 
109 	if (beacon)
110 		wlcore_set_pending_regdomain_ch(wl, (u16)desc->channel,
111 						status->band);
112 }
113 
114 static int wl1271_rx_handle_data(struct wl1271 *wl, u8 *data, u32 length,
115 				 enum wl_rx_buf_align rx_align, u8 *hlid)
116 {
117 	struct wl1271_rx_descriptor *desc;
118 	struct sk_buff *skb;
119 	struct ieee80211_hdr *hdr;
120 	u8 beacon = 0;
121 	u8 is_data = 0;
122 	u8 reserved = 0, offset_to_data = 0;
123 	u16 seq_num;
124 	u32 pkt_data_len;
125 
126 	/*
127 	 * In PLT mode we seem to get frames and mac80211 warns about them,
128 	 * workaround this by not retrieving them at all.
129 	 */
130 	if (unlikely(wl->plt))
131 		return -EINVAL;
132 
133 	pkt_data_len = wlcore_hw_get_rx_packet_len(wl, data, length);
134 	if (!pkt_data_len) {
135 		wl1271_error("Invalid packet arrived from HW. length %d",
136 			     length);
137 		return -EINVAL;
138 	}
139 
140 	if (rx_align == WLCORE_RX_BUF_UNALIGNED)
141 		reserved = RX_BUF_ALIGN;
142 	else if (rx_align == WLCORE_RX_BUF_PADDED)
143 		offset_to_data = RX_BUF_ALIGN;
144 
145 	/* the data read starts with the descriptor */
146 	desc = (struct wl1271_rx_descriptor *) data;
147 
148 	if (desc->packet_class == WL12XX_RX_CLASS_LOGGER) {
149 		size_t len = length - sizeof(*desc);
150 		wl12xx_copy_fwlog(wl, data + sizeof(*desc), len);
151 		return 0;
152 	}
153 
154 	/* discard corrupted packets */
155 	if (desc->status & WL1271_RX_DESC_DECRYPT_FAIL) {
156 		hdr = (void *)(data + sizeof(*desc) + offset_to_data);
157 		wl1271_warning("corrupted packet in RX: status: 0x%x len: %d",
158 			       desc->status & WL1271_RX_DESC_STATUS_MASK,
159 			       pkt_data_len);
160 		wl1271_dump((DEBUG_RX|DEBUG_CMD), "PKT: ", data + sizeof(*desc),
161 			    min(pkt_data_len,
162 				ieee80211_hdrlen(hdr->frame_control)));
163 		return -EINVAL;
164 	}
165 
166 	/* skb length not including rx descriptor */
167 	skb = __dev_alloc_skb(pkt_data_len + reserved, GFP_KERNEL);
168 	if (!skb) {
169 		wl1271_error("Couldn't allocate RX frame");
170 		return -ENOMEM;
171 	}
172 
173 	/* reserve the unaligned payload(if any) */
174 	skb_reserve(skb, reserved);
175 
176 	/*
177 	 * Copy packets from aggregation buffer to the skbs without rx
178 	 * descriptor and with packet payload aligned care. In case of unaligned
179 	 * packets copy the packets in offset of 2 bytes guarantee IP header
180 	 * payload aligned to 4 bytes.
181 	 */
182 	skb_put_data(skb, data + sizeof(*desc), pkt_data_len);
183 	if (rx_align == WLCORE_RX_BUF_PADDED)
184 		skb_pull(skb, RX_BUF_ALIGN);
185 
186 	*hlid = desc->hlid;
187 
188 	hdr = (struct ieee80211_hdr *)skb->data;
189 	if (ieee80211_is_beacon(hdr->frame_control))
190 		beacon = 1;
191 	if (ieee80211_is_data_present(hdr->frame_control))
192 		is_data = 1;
193 
194 	wl1271_rx_status(wl, desc, IEEE80211_SKB_RXCB(skb), beacon);
195 	wlcore_hw_set_rx_csum(wl, desc, skb);
196 
197 	seq_num = (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
198 	wl1271_debug(DEBUG_RX, "rx skb 0x%p: %d B %s seq %d hlid %d", skb,
199 		     skb->len - desc->pad_len,
200 		     beacon ? "beacon" : "",
201 		     seq_num, *hlid);
202 
203 	skb_queue_tail(&wl->deferred_rx_queue, skb);
204 	queue_work(wl->freezable_wq, &wl->netstack_work);
205 
206 	return is_data;
207 }
208 
209 int wlcore_rx(struct wl1271 *wl, struct wl_fw_status *status)
210 {
211 	unsigned long active_hlids[BITS_TO_LONGS(WLCORE_MAX_LINKS)] = {0};
212 	u32 buf_size;
213 	u32 fw_rx_counter = status->fw_rx_counter % wl->num_rx_desc;
214 	u32 drv_rx_counter = wl->rx_counter % wl->num_rx_desc;
215 	u32 rx_counter;
216 	u32 pkt_len, align_pkt_len;
217 	u32 pkt_offset, des;
218 	u8 hlid;
219 	enum wl_rx_buf_align rx_align;
220 	int ret = 0;
221 
222 	/* update rates per link */
223 	hlid = status->counters.hlid;
224 
225 	if (hlid < WLCORE_MAX_LINKS)
226 		wl->links[hlid].fw_rate_mbps =
227 				status->counters.tx_last_rate_mbps;
228 
229 	while (drv_rx_counter != fw_rx_counter) {
230 		buf_size = 0;
231 		rx_counter = drv_rx_counter;
232 		while (rx_counter != fw_rx_counter) {
233 			des = le32_to_cpu(status->rx_pkt_descs[rx_counter]);
234 			pkt_len = wlcore_rx_get_buf_size(wl, des);
235 			align_pkt_len = wlcore_rx_get_align_buf_size(wl,
236 								     pkt_len);
237 			if (buf_size + align_pkt_len > wl->aggr_buf_size)
238 				break;
239 			buf_size += align_pkt_len;
240 			rx_counter++;
241 			rx_counter %= wl->num_rx_desc;
242 		}
243 
244 		if (buf_size == 0) {
245 			wl1271_warning("received empty data");
246 			break;
247 		}
248 
249 		/* Read all available packets at once */
250 		des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
251 		ret = wlcore_hw_prepare_read(wl, des, buf_size);
252 		if (ret < 0)
253 			goto out;
254 
255 		ret = wlcore_read_data(wl, REG_SLV_MEM_DATA, wl->aggr_buf,
256 				       buf_size, true);
257 		if (ret < 0)
258 			goto out;
259 
260 		/* Split data into separate packets */
261 		pkt_offset = 0;
262 		while (pkt_offset < buf_size) {
263 			des = le32_to_cpu(status->rx_pkt_descs[drv_rx_counter]);
264 			pkt_len = wlcore_rx_get_buf_size(wl, des);
265 			rx_align = wlcore_hw_get_rx_buf_align(wl, des);
266 
267 			/*
268 			 * the handle data call can only fail in memory-outage
269 			 * conditions, in that case the received frame will just
270 			 * be dropped.
271 			 */
272 			if (wl1271_rx_handle_data(wl,
273 						  wl->aggr_buf + pkt_offset,
274 						  pkt_len, rx_align,
275 						  &hlid) == 1) {
276 				if (hlid < wl->num_links)
277 					__set_bit(hlid, active_hlids);
278 				else
279 					WARN(1,
280 					     "hlid (%d) exceeded MAX_LINKS\n",
281 					     hlid);
282 			}
283 
284 			wl->rx_counter++;
285 			drv_rx_counter++;
286 			drv_rx_counter %= wl->num_rx_desc;
287 			pkt_offset += wlcore_rx_get_align_buf_size(wl, pkt_len);
288 		}
289 	}
290 
291 	/*
292 	 * Write the driver's packet counter to the FW. This is only required
293 	 * for older hardware revisions
294 	 */
295 	if (wl->quirks & WLCORE_QUIRK_END_OF_TRANSACTION) {
296 		ret = wlcore_write32(wl, WL12XX_REG_RX_DRIVER_COUNTER,
297 				     wl->rx_counter);
298 		if (ret < 0)
299 			goto out;
300 	}
301 
302 	wl12xx_rearm_rx_streaming(wl, active_hlids);
303 
304 out:
305 	return ret;
306 }
307 
308 #ifdef CONFIG_PM
309 int wl1271_rx_filter_enable(struct wl1271 *wl,
310 			    int index, bool enable,
311 			    struct wl12xx_rx_filter *filter)
312 {
313 	int ret;
314 
315 	if (!!test_bit(index, wl->rx_filter_enabled) == enable) {
316 		wl1271_warning("Request to enable an already "
317 			     "enabled rx filter %d", index);
318 		return 0;
319 	}
320 
321 	ret = wl1271_acx_set_rx_filter(wl, index, enable, filter);
322 
323 	if (ret) {
324 		wl1271_error("Failed to %s rx data filter %d (err=%d)",
325 			     enable ? "enable" : "disable", index, ret);
326 		return ret;
327 	}
328 
329 	if (enable)
330 		__set_bit(index, wl->rx_filter_enabled);
331 	else
332 		__clear_bit(index, wl->rx_filter_enabled);
333 
334 	return 0;
335 }
336 
337 int wl1271_rx_filter_clear_all(struct wl1271 *wl)
338 {
339 	int i, ret = 0;
340 
341 	for (i = 0; i < WL1271_MAX_RX_FILTERS; i++) {
342 		if (!test_bit(i, wl->rx_filter_enabled))
343 			continue;
344 		ret = wl1271_rx_filter_enable(wl, i, 0, NULL);
345 		if (ret)
346 			goto out;
347 	}
348 
349 out:
350 	return ret;
351 }
352 #endif /* CONFIG_PM */
353